The present invention relates to a front structure for a vehicle.
A front structure for a vehicle such as an automobile, of a related art is shown in FIGS. 6 and 7. FIG. 6 illustrates front side member 1 extending in a fore-and-aft direction of the vehicle as indicated by arrow 2, in which only one of a pair of front side members 1 is illustrated. Bumper member 3 extending in a lateral direction perpendicular to fore-and-aft direction 2 is connected with front ends of front side members 1. Subframe 4 extends below each of front side members 1 in fore-and-aft direction 2. Subframe 4 is connected at least at a front end portion thereof with a front end portion of front side member 1 via bracket 5. Bumper member 3 includes bumper stay 6, bumper armature 7 mounted to a front side of bumper stay 6, and a bumper fascia covering a front side of bumper armature 7. Bumper stay 6 is deformable to absorb an impact load which is applied thereto from the front side of the vehicle. The bumper fascia is made of resin and forms a front end surface of bumper member 3. Tie-down hook 8 for holding a tow rope is disposed on the front end portion of front side member 1. Specifically, tie-down hook 8 is positioned forward bracket 5 and rearward the front end of front side member 1 and the front outer surface of bumper member 3. Tie-down hook 8 is secured to the front end portion of front side member 1 by means of bolts 9 as shown in FIG. 7.
Japanese Patent Application First Publication No. 9-99867 discloses an automotive front structure including a pair of front side members extending in a fore-and-aft direction of the vehicle on left and right sides of the front compartment. Subframes are disposed below the front side members and support automotive units such as a power unit and a suspension unit. A front bulkhead as a first cross member extending in a lateral direction of the vehicle perpendicular to the fore-and-aft direction is connected at left and right ends thereof with lower surfaces of front end portions of the front side members. Front end portions of the subframes are located rearward the left and right ends of the first cross member and connected with the lower surfaces of the front side members via brackets. A bumper mounting member as a second cross member extending in the lateral direction of the vehicle is fixed to front ends of the front side members. The bumper mounting bracket is used for mounting a bumper member.
If an impact load is applied from the front side of the vehicle to such a front structure as described in the related arts, the impact load will be transmitted to the front side members in the longitudinal direction of the vehicle via the bumper member so that the front side members may be deformed into a corrugated state to thereby absorb the impact energy.
However, the impact load acting on the front end portion of the front side members will be downward offset and transmitted to the subframes via the brackets. This will deteriorate the efficiency of transmission of the impact load. Further, in these related arts, the front ends of the subframes are located rearward offset from the front ends of the front side members. This will cause delay in rise-up of a collapse reaction force in the subframes as compared to that of the front side members, which deteriorates the efficiency of absorption of the impact energy. Further, in the related art of FIGS. 6 and 7, no cross member extending in the lateral direction of the vehicle is provided in the vicinity of a connecting portion between the front end portion of the subframe and the front side member. Therefore, many reinforcements must be used in the front side member in order to enhance the rigidity of the connecting portion. Furthermore, in the related art described in the above Japanese Patent Application First Publication No. 9-99867, the bumper member is located forward the first cross member which defines a front end of a power unit installation room in a front compartment of the vehicle. The front compartment, therefore, overhangs forward to a considerable extent. This will adversely affect freedom of design of the vehicle front compartment.
It would threrefore be desirable to provide a vehicle front structure capable of effectively dispersing an impact load which is applied from the front side of the vehicle to front side members, to subframes, and capable of improving rigidity of a connecting portion between the front side members and front end portions of the subframes. This can serve for omitting reinforcements from the front side members. Further, it would be desirable to provide a vehicle front structure in which the front side members and the subframes can absorb the impact energy from an initial stage of application of the impact load to the vehicle front structure. This can serve for enhancing the efficiency of absorption of the impact energy at the vehicle front structure.
In one aspect of the present invention, there is provided a front structure for a vehicle, the structure comprising:
a pair of front side members extending in a fore-and-aft direction of the vehicle and including a first front end portion;
a pair of subframes extending along the front side members on a lower side thereof, said pair of subframes each including a second front end portion connected with said first front end portion at a connecting portion therebetween; and
a tie-down hook disposed on the connecting portion between said first front end portion and said second front end portion, said tie-down hook including a lower portion positioned at substantially same height as said second front end portion.
In a further aspect of the present invention, there is provided a front structure for a vehicle, the structure comprising:
a pair of front side members extending in a fore-and-aft direction of the vehicle, said pair of front side members each including a first front end portion with a first leading end;
a pair of subframes extending along the front side members on a lower side thereof, said pair of subframes each including a second front end portion with a second leading end, which is connected with said first front end portion; and
a first cross member extending in a lateral direction extending perpendicular to the fore-and-aft direction of the vehicle, said first cross member being connected with said first front end portion, said first cross member being placed in substantially same height as said second front end portion, said first cross member including a front end,
wherein said second leading end is substantially aligned with said first leading end in the fore-and-aft direction of the vehicle, and said front end of the first cross member is located forward offset from said first leading end.
In a still further aspect of the present invention, there is provided a front structure for a vehicle, the structure comprising:
a pair of front side members extending in a fore-and-aft direction of the vehicle, said pair of front side members each including a first front end portion with a first leading end;
a pair of subframes extending along the front side members on a lower side thereof, said pair of subframes each including a second front end portion with a second leading end, said second front end portion being connected with said first front end portion via a connecting portion therebetween; and
an abutment member connected with the subframes via the connecting portion between said first and second front end portions, said abutment member including a front end forward offset from said first and second leading ends, and a portion placed at substantially same height as said second front end portion.